The paper “Increased Vital and Total Lung Capacities in Tibetan Compared to Han Residents of Lhasa” (American Journal of Physical Anthropology [1991]: 341–351) included a scatterplot of vital capacity (y) versus chest circumference (x) for a sample of 16 Tibetan natives, from which the following data were read:

a. Construct a scatterplot. What does it suggest about the nature of the relationship between x and y?

b. The summary quantities are

Verify that the equation of the least-squares line is ŷ = −451 + 0.1123x, and draw this line on your scatterplot.

c. On average, roughly what change in vital capacity is associated with a 1-cm increase in chest circumference? with a 10-cm increase?

d. What vital capacity would you predict for a Tibetan native whose chest circumference is 85 cm?

e. Is vital capacity completely determined by chest circumference? Explain.

Transcribed Image Text:

X X y 79.4 4.3 87.0 6.1 81.8 81.8 82.3 83.7 84.3 84.3 85.2 4.7 5.0 4.9 4.4 5.0 4.6 4.8 87.3 87.7 88.1 88.1 88.6 89.0 89.5 4.7 5.7 5.7 5.2 5.5 5.0 5.3